Su Huiping, Su Zhe, Pan Lili, Wang Li, Xu Zhongwei, Peng Gang, Li Xianglei
Department of Endocrinology, Shenzhen Children's Hospital, No. 7019, Yitian Road, Futian District, 518038, Shenzhen, Guangdong Province, People's Republic of China.
Department of Adolescent Gynecology, Shenzhen Children's Hospital, Shenzhen, China.
BMC Pediatr. 2020 Jul 29;20(1):356. doi: 10.1186/s12887-020-02256-w.
In isolated premature thelarche (IPT) girls, bone age (BA) is considered consistent with chronological age. However, some IPT girls confirmed by gonadotropin-releasing hormone (GnRH) stimulation test could show another trend. We analysed BA and possible potentiating factors in a selected group of girls aged 4-8 years with IPT.
IPT girls confirmed by GnRH stimulation test aged 4-8 years hospitalized from January 2015 to April 2018 at Shenzhen Children's Hospital were included in this retrospective study. They were divided into two groups with advanced BA of 2 years as the cut-off. Body mass index (BMI) and hormone levels were the main outcome measures, and regression analysis was used to identify independent risk factors. IPT girls were divided into subgroups according to the levels of BMI standard deviation score (SDS), insulin-like growth factor-1 (IGF-1) SDS and dehydroepiandrosterone sulfate (DHEAS) SDS for comparisons of advanced BA.
Overall, 423 subjects were included and classified into the advanced BA group (48.7%, n = 206) and control group (51.3%, n = 217). The advanced BA group had significantly higher BMI SDS, serum DHEAS SDS, IGF-1 SDS, androstenedione and fasting insulin and significantly lower sex hormone binding globulin (all p < 0.001). Serum IGF-1 SDS (OR = 1.926, p<0.001), BMI SDS (OR = 1.427, p = 0.001) and DHEAS SDS (OR = 1.131, p = 0.005) were independent risk factors for significantly advanced BA. In the multiple linear regression model, serum IGF-1 SDS, BMI SDS and DHEAS SDS were the strongest predictors of advanced BA, accounting for 19.3% of the variance. According to BMI, 423 patients were classified into three groups: normal weight (56.03%, n = 237), overweight (19.15%, n = 81) and obesity (24.82%, n = 105). The proportion of advanced BA in obesity group was significantly higher than those of normal weight and overweight groups (χ = 18.088, p<0.001). In the subgroup with normal weight, higher serum IGF-1 SDS (p = 0.009) and DHEAS SDS (p = 0.003) affected BA advancement independent of BMI SDS.
Girls with IPT confirmed by GnRH stimulation test aged 4-8 years might have significantly advanced BA. Obesity was highly associated with advanced BA. Age-specific serum IGF-1 SDS and DHEAS SDS were risk factors for BA advancement independent of BMI.
在单纯性乳房早发育（IPT）女童中，骨龄（BA）被认为与实际年龄相符。然而，一些经促性腺激素释放激素（GnRH）刺激试验确诊的IPT女童可能呈现出另一种趋势。我们分析了一组4至8岁IPT女童的骨龄及可能的促发因素。
本回顾性研究纳入了2015年1月至2018年4月在深圳儿童医院住院的、经GnRH刺激试验确诊的4至8岁IPT女童。以骨龄超前2岁为界将她们分为两组。主要观察指标为体重指数（BMI）和激素水平，并采用回归分析确定独立危险因素。根据BMI标准差评分（SDS）、胰岛素样生长因子-1（IGF-1）SDS和硫酸脱氢表雄酮（DHEAS）SDS水平将IPT女童分为亚组，以比较骨龄超前情况。
共纳入423例受试者，分为骨龄超前组（48.7%，n = 206）和对照组（51.3%，n = 217）。骨龄超前组的BMI SDS、血清DHEAS SDS、IGF-1 SDS、雄烯二酮和空腹胰岛素显著更高，而性激素结合球蛋白显著更低（均p < 0.001）。血清IGF-1 SDS（OR = 1.926，p < 0.001）、BMI SDS（OR = 1.427，p = 0.001）和DHEAS SDS（OR = 1.131，p = 0.005）是骨龄显著超前的独立危险因素。在多元线性回归模型中，血清IGF-1 SDS、BMI SDS和DHEAS SDS是骨龄超前的最强预测因素，解释了19.3%的变异。根据BMI，423例患者分为三组：正常体重（56.03%，n = 237）、超重（19.15%，n = 81）和肥胖（24.82%，n = 105）。肥胖组骨龄超前的比例显著高于正常体重组和超重组（χ = 18.088，p < 0.001）。在正常体重亚组中，较高的血清IGF-1 SDS（p = 0.009）和DHEAS SDS（p = 0.003）独立于BMI SDS影响骨龄进展。
经GnRH刺激试验确诊的4至8岁IPT女童可能骨龄显著超前。肥胖与骨龄超前高度相关。特定年龄的血清IGF-1 SDS和DHEAS SDS是独立于BMI的骨龄进展危险因素。
